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Amount of the fee that accompanies borrowing money under the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Debt Instrument, Variable Interest Rate, Adjustment, Period

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Borrowings - Additional Information (Details) $ in Thousands, ¥ in Millions	Feb. 07, 2024 USD ($)	Feb. 06, 2024 USD ($)	Feb. 05, 2024 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2024 CNY (¥)	Feb. 07, 2024 CNY (¥)	Feb. 06, 2024 CNY (¥)	Dec. 31, 2023 USD ($)
Short-Term Debt [Line Items]
Restricted cash, current				$ 100,000				$ 0
Short-term debts				$ 48,273				$ 0
Weighted average interest rate per annum				3.10%	3.10%
Maximum guarantor obligation		$ 42,000					¥ 300.0
Guarantor obligation term		3 years
Bank of China Working Capital Loan
Short-Term Debt [Line Items]
Debt instrument fee			$ 700
Ningbo Bank Working Capital Loan Facility \| Loans Payable
Short-Term Debt [Line Items]
Maximum borrowing capacity		$ 22,500					160.0
Ningbo Bank Working Capital Loan Facility \| Zai Lab Suzhou Company Limited \| Loans Payable
Short-Term Debt [Line Items]
Maximum borrowing capacity		$ 32,400					¥ 230.3
Loans Payable \| Bank of China Working Capital Loan
Short-Term Debt [Line Items]
Short-term debts				$ 34,179
Weighted average interest rate per annum				2.95%	2.95%
Loans Payable \| Bank of China Working Capital Loan \| Zai Lab (Shanghai) Co., Ltd.
Short-Term Debt [Line Items]
Debt instrument term	1 year
Loan face amount	$ 47,800					¥ 340.0
Short-term debts				$ 34,200	¥ 242.5
Weighted average interest rate per annum	2.95%					2.95%
Floating interest rate adjustment period	6 months
Loans Payable \| SPD Bank Working Capital Loan
Short-Term Debt [Line Items]
Short-term debts				$ 14,094
Weighted average interest rate per annum				3.45%	3.45%
Loans Payable \| SPD Bank Working Capital Loan \| Zai Lab (Shanghai) Co., Ltd.
Short-Term Debt [Line Items]
Debt instrument term		1 year
Loan face amount				$ 14,100	¥ 100.0
Fixed interest rate		3.45%					3.45%
Standby Letters of Credit \| Bank of China Working Capital Loan
Short-Term Debt [Line Items]
Maximum borrowing capacity			$ 100,000
Debt instrument term			1 year
Letters of credit outstanding		$ 50,000